Earth-like planets abound in red dwarf systems

The nearest Earth-like planet that could support liquid water may be much closer than first believed, according to new research by the Harvard-Smithsonian Center for Astrophysics.

"We thought we would have to search vast distances to find an Earth-like planet," said Harvard astronomer and lead author Courtney Dressing in a statement. "Now we realize another Earth is probably in our own backyard, waiting to be spotted."

The team analyzed data from NASA's Kepler space telescope to look at red dwarf stars, slow-growing solar furnaces that make up around three-quarters of the stars in our galaxy. These have been considered poor candidates for Earth-like planets, but the team found 6 per cent of red dwarfs could harbor conditions for life as we know it.

With at least 75 billion available red dwarfs, that adds up to a lot of planets suitable for life. And based on this simple survey, Dressing found 95 suitable planets, three of which being a similar size to Earth and warm enough for liquid water, with the nearest just 13 light years away.

Because red dwarfs are long-lived, slow-burning stars, some of the Earth-like planets found could be significantly older than our own. If the pattern of life has taken a similar course, this could lead to civilizations much more advanced than our own. "We might find an Earth that's 10 billion years old," speculated coauthor David Charbonneau.

But there's a world of difference (pun unintended) between finding a planet that's well-positioned to support humanity and analysis of its atmosphere to find out if it really could. It may be unlikely that we'll find planets out there that could support unaided humans, but given a closer examination by instruments such as the Giant Magellan Telescope and James Webb Space Telescope, who knows? ®